US6595041B2 - Method and apparatus for magnetic levitation - Google Patents

Method and apparatus for magnetic levitation Download PDF

Info

Publication number
US6595041B2
US6595041B2 US09/892,437 US89243701A US6595041B2 US 6595041 B2 US6595041 B2 US 6595041B2 US 89243701 A US89243701 A US 89243701A US 6595041 B2 US6595041 B2 US 6595041B2
Authority
US
United States
Prior art keywords
electromagnet
hall effect
magnet
suspension
magnetic levitation
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
US09/892,437
Other versions
US20020124765A1 (en
Inventor
Brian Nils Hansen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US09/892,437 priority Critical patent/US6595041B2/en
Publication of US20020124765A1 publication Critical patent/US20020124765A1/en
Application granted granted Critical
Publication of US6595041B2 publication Critical patent/US6595041B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01G—WEIGHING
    • G01G7/00—Weighing apparatus wherein the balancing is effected by magnetic, electromagnetic, or electrostatic action, or by means not provided for in the preceding groups
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C32/00—Bearings not otherwise provided for
    • F16C32/04—Bearings not otherwise provided for using magnetic or electric supporting means
    • F16C32/0406—Magnetic bearings
    • F16C32/044—Active magnetic bearings
    • F16C32/0444—Details of devices to control the actuation of the electromagnets
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C2326/00—Articles relating to transporting
    • F16C2326/10—Railway vehicles
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N13/00—Investigating surface or boundary effects, e.g. wetting power; Investigating diffusion effects; Analysing materials by determining surface, boundary, or diffusion effects
    • G01N2013/006—Dissolution of tablets or the like
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N9/00—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity
    • G01N9/08—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity by measuring buoyant force of solid materials by weighing both in air and in a liquid
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S73/00—Measuring and testing
    • Y10S73/03—Hall effect

Definitions

  • the present invention relates to methods and apparatus for magnetic levitation or suspension of an object, part or magnet at a desired position that is electronically stabilized with Hall effect sensors.
  • Friction can be minimized by magnetic levitation for motors, turbines, generators, trains, projectile guns, etc.
  • Magnetic suspension or levitation is an important technique to measure force on an object in a wind tunnel. Wires, cables etc. used to suspend an object in a wind tunnel will interfere with the force measurement.
  • Some fluid density measurements require magnetic suspension to prevent surface tension from interfering with buoy suspension line.
  • High pressure fluid density measurement require magnetic suspension to measure the force on a buoy through the walls of a high pressure vessel.
  • a number of magnetic levitation devices have been built to demonstrate a floating object with no visible support, which spectacular feature is commonly known to the general public via the manufacture of various novelty or entertainment devices.
  • Magnetic levitation can be accomplished in an active system using an electromagnet, position sensor, and feedback control circuit.
  • the electromagnet is driven with an electrical current which is used to maintain the levitated object in a stable position at a general location situated beneath the electromagnet.
  • the position sensor detects the position of the levitated object for the feedback circuit.
  • the feedback circuit controls the current in the electromagnet to maintain a given position.
  • Stable magnetic levitation is maintained in the system by increasing the lifting current in the electromagnet when the object falls away from the electromagnet and the lifting current decreases when the levitated object moves up towards the electromagnet.
  • a number of different position sensors are currently used to maintain stable magnetic levitation.
  • the position of a levitated object can be detected optically when a light beam is interrupted and the optical detector changes the current in the lifting coil. In the case of measuring fluid properties or fluid conditions, this limits fluid measurement to optically transparent fluids and vessels, where the range of possible fluid measurements include, but are not limited to, flowrate, density, viscosity, phase change, and phase equilibria properties.
  • a liquid meniscus or droplet can also interfere with the light beam.
  • Inductive and capacitive detectors are also limited by the materials that the fluid containment vessel is made of.
  • Hall effect sensors can detect the position of a permanent magnet in tubes made of metals, ceramics, glass, sapphire, and any material that will allow some detectable magnetic field to penetrate the material. With the recent development of low cost amplified hall effect sensors and power amplifiers this technology is easily adapted to a wide variety of applications.
  • FIG. 1 sets forth a first embodiment of the apparatus according to the present invention.
  • FIG. 2 sets forth an embodiment of the electronic control circuit of the apparatus set forth in FIG. 1 .
  • a hall effect sensor or hall effect sensors measure the position of a permanent magnet.
  • the hall effect sensors control the current in an electromagnet to maintain the desired position between two permanent magnets.
  • the present invention also relates to apparatus particularly adapted for use in connection with the described methods of magnetic levitation.
  • FIG. 1 An example of such an apparatus according to the invention is set forth in FIG. 1 .
  • the cylindrical permanent magnet 1 is attracted to the ring permanent magnet 2 .
  • the hall effect sensors 3 detect the distance between the permanent magnets to maintain the desired distance with the current in the electromagnet 6 .
  • the electronic balance 4 measures the lifting force required for the cylindrical permanent magnet 1 suspended in the sapphire tube 5 .
  • the suspended holder 7 can be used to hold a solute for solubility measurement. Solubility measurement is performed when the solute dissolves in the solvent contained in the sapphire tube and the electronic balance measures the change in force.
  • the circuit shown in FIG. 2 can be used to control the position between the permanent magnets in FIG. 1 .
  • the hall effect sensors 3 provide position information to the amplifier circuit 8 which controls the electrical current in the electromagnet 6 .
  • the position control circuit 9 can be used to change the position between the magnets, maintain a position that provides electromagnet coil current that is near zero, or cause the magnets to oscillate, etc.
  • the circuit in 10 can be used to filter out oscillations and maintain high degree of stability, or measure lifting force for a given position.
  • the magnetic levitation system shown in FIG. 1 was used to measure the density of freon R-116(hexafluoroethane) at ambient temperature in a high pressure environment that ranges from 600 PSI to 1000 PSI.
  • the solubility and saturated density for the binary system of R-116 and Iron Hexafluoroacetylacetonate was also measured in this pressure range.

Abstract

A method to maintain magnetic levitation that is stabilized by means of Hall effect sensors is disclosed. The method and device comprising a Hall effect sensor or sensors used to control an electromagnet to maintain the position between two magnets or objects. The present invention has been used to suspend a magnet in a high pressure tube that is magnetically coupled to a magnet outside the tube connected to an analytical balance that can accurately measure the force on the magnet inside the tube. This force measurement can be used to determine fluid density, flow, viscosity, and solubility. This magnetic levitation method also has application for other devices such as motors, generators, trains, turbines, wind tunnels, and entertainment devices.

Description

This application claims the benefit of Provisional application Ser. No. 60/214,359, filed Jun. 28, 2000.
FIELD OF THE INVENTION
The present invention relates to methods and apparatus for magnetic levitation or suspension of an object, part or magnet at a desired position that is electronically stabilized with Hall effect sensors.
BACKGROUND OF THE INVENTION
There are many applications for utilizing magnetic levitation to minimize friction, make force measurement, design, and entertaining devices. Friction can be minimized by magnetic levitation for motors, turbines, generators, trains, projectile guns, etc. Magnetic suspension or levitation is an important technique to measure force on an object in a wind tunnel. Wires, cables etc. used to suspend an object in a wind tunnel will interfere with the force measurement. Some fluid density measurements require magnetic suspension to prevent surface tension from interfering with buoy suspension line. High pressure fluid density measurement require magnetic suspension to measure the force on a buoy through the walls of a high pressure vessel. A number of magnetic levitation devices have been built to demonstrate a floating object with no visible support, which spectacular feature is commonly known to the general public via the manufacture of various novelty or entertainment devices.
There are many applications for magnetic levitation that require position sensing and feedback control. Stable magnetic levitation or suspension can be achieved in a totally passive system using a superconductor. However, in some cases it is not possible or practical to use a passive system. Magnetic levitation can be accomplished in an active system using an electromagnet, position sensor, and feedback control circuit. The electromagnet is driven with an electrical current which is used to maintain the levitated object in a stable position at a general location situated beneath the electromagnet. The position sensor detects the position of the levitated object for the feedback circuit. The feedback circuit controls the current in the electromagnet to maintain a given position. Stable magnetic levitation is maintained in the system by increasing the lifting current in the electromagnet when the object falls away from the electromagnet and the lifting current decreases when the levitated object moves up towards the electromagnet. A number of different position sensors are currently used to maintain stable magnetic levitation. The position of a levitated object can be detected optically when a light beam is interrupted and the optical detector changes the current in the lifting coil. In the case of measuring fluid properties or fluid conditions, this limits fluid measurement to optically transparent fluids and vessels, where the range of possible fluid measurements include, but are not limited to, flowrate, density, viscosity, phase change, and phase equilibria properties. A liquid meniscus or droplet can also interfere with the light beam. Inductive and capacitive detectors are also limited by the materials that the fluid containment vessel is made of. Hall effect sensors can detect the position of a permanent magnet in tubes made of metals, ceramics, glass, sapphire, and any material that will allow some detectable magnetic field to penetrate the material. With the recent development of low cost amplified hall effect sensors and power amplifiers this technology is easily adapted to a wide variety of applications.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide methods and apparatus for achieving electronically stabilized magnetic suspension of objects, parts or magnets at desired positions using hall effect sensors. It is a further objective of the present invention to provide methods and apparatus for, but not limited to, fluid property measurement, wind tunnel measurements, trains, monorails, transportation equipment, toys, novelty or entertainment devices etc.
BRIEF DESCRIPTION OF THE DRAWINGS
The following detailed description will be more fully understood in view of the drawing in which:
FIG. 1 sets forth a first embodiment of the apparatus according to the present invention; and
FIG. 2 sets forth an embodiment of the electronic control circuit of the apparatus set forth in FIG. 1.
DETAILED DESCRIPTION
In accordance with the present methods for maintaining stable magnetic levitation, a hall effect sensor or hall effect sensors measure the position of a permanent magnet. The hall effect sensors control the current in an electromagnet to maintain the desired position between two permanent magnets. The present invention also relates to apparatus particularly adapted for use in connection with the described methods of magnetic levitation.
An example of such an apparatus according to the invention is set forth in FIG. 1. With reference to FIG. 1, the cylindrical permanent magnet 1 is attracted to the ring permanent magnet 2. The hall effect sensors 3 detect the distance between the permanent magnets to maintain the desired distance with the current in the electromagnet 6. The electronic balance 4 measures the lifting force required for the cylindrical permanent magnet 1 suspended in the sapphire tube 5. The suspended holder 7 can be used to hold a solute for solubility measurement. Solubility measurement is performed when the solute dissolves in the solvent contained in the sapphire tube and the electronic balance measures the change in force.
The circuit shown in FIG. 2 can be used to control the position between the permanent magnets in FIG. 1. With reference to FIG. 2, the hall effect sensors 3 provide position information to the amplifier circuit 8 which controls the electrical current in the electromagnet 6. The position control circuit 9 can be used to change the position between the magnets, maintain a position that provides electromagnet coil current that is near zero, or cause the magnets to oscillate, etc. The circuit in 10 can be used to filter out oscillations and maintain high degree of stability, or measure lifting force for a given position.
EXAMPLE
The magnetic levitation system shown in FIG. 1 was used to measure the density of freon R-116(hexafluoroethane) at ambient temperature in a high pressure environment that ranges from 600 PSI to 1000 PSI. The solubility and saturated density for the binary system of R-116 and Iron Hexafluoroacetylacetonate was also measured in this pressure range.

Claims (10)

What is claimed:
1. A method achieving an active system for magnetic levitation or suspension of a suspended object, part or magnet, comprising: an electromagnet for levitating or suspending said object, part or magnet at a known desired or maintained position, which electromagnet is controlled by two or more hall effect sensors wherein the two or more hall effect sensors are used to reduce or cancel signals resultant from any lateral movement of said suspended object, part or magnet, thereby providing better vertical control of said position of said suspended object, part or magnet.
2. A method achieving an active system for magnetic levitation or suspension of a suspended object, part or magnet, comprising: an electromagnet that is controlled by one or more hall effect sensors wherein levitation system is used to maintain the position between two permanent magnets that are oriented to have an attractive force.
3. The method of claim 2 wherein the electromagnet maintains a position between a ring shaped permanent magnet and solid permanent magnet.
4. The method of claim 2 further comprising the use, of an electronic amplifier or amplifiers to amplify the signal from the hall effect sensor to control an electromagnet or electromagnets.
5. The method of claim 4 wherein the electromagnets maintain a position between the permanent magnets such that the current in the electromagnet approaches zero.
6. The method of claim 4 wherein the signal from the hall effect sensor and the amplifier is used to change the position between said two permanent magnets.
7. The method of claim 4 wherein the magnetic suspension is used to measure the force on a suspended object.
8. The method of claim 4 wherein the magnetic suspension is used in reducing friction by means of non-contact bearings in mechanical machine and machinery applications consisting of motors, generators, trains, turbines and vacuum pumps.
9. A method that uses magnetic levitation or suspension to measure properties of a fluid including, but not limited to, flow rate, density, viscosity, and phase equilibria of a static or mobile fluid that is either contained in or flowing thru a tube further comprising an electromagnet or electromagnets controlled by two or more hall effect sensors, using an amplifier or amplifiers to amplify the signal from said sensors, further utilizing a ring shaped permanent magnet and electromagnet connected to a force measurement device or balance to measure the force on a permanent magnet suspended in said tube.
10. A method that uses magnetic levitation or suspension to measure the forces on an object suspended in a wind tunnel comprising an electromagnet(s) controlled by two or more hall effect sensors, further comprising the use of an amplifier(s) to amplify the signal from said hall effect sensors and power the electromagnet(s).
US09/892,437 2000-06-28 2001-06-28 Method and apparatus for magnetic levitation Expired - Fee Related US6595041B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US09/892,437 US6595041B2 (en) 2000-06-28 2001-06-28 Method and apparatus for magnetic levitation

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US21435900P 2000-06-28 2000-06-28
US09/892,437 US6595041B2 (en) 2000-06-28 2001-06-28 Method and apparatus for magnetic levitation

Publications (2)

Publication Number Publication Date
US20020124765A1 US20020124765A1 (en) 2002-09-12
US6595041B2 true US6595041B2 (en) 2003-07-22

Family

ID=26908913

Family Applications (1)

Application Number Title Priority Date Filing Date
US09/892,437 Expired - Fee Related US6595041B2 (en) 2000-06-28 2001-06-28 Method and apparatus for magnetic levitation

Country Status (1)

Country Link
US (1) US6595041B2 (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080218929A1 (en) * 2002-09-27 2008-09-11 Harold Davis Magnetic levitation apparatus
CN102680356A (en) * 2012-05-25 2012-09-19 东北大学 Density measuring device and method based on electromagnetic suspension
DE102016205377B3 (en) * 2016-03-31 2017-08-03 Festo Ag & Co. Kg Measuring arrangement and method for operating a measuring arrangement
CN107589141A (en) * 2017-09-06 2018-01-16 南京工业大学 One kind is used for edible oil quality detection method based on magnetic levitation technology detection object density
WO2018094401A1 (en) 2016-11-21 2018-05-24 Flyte Llc Interactive and customizable device using magnetic levitation
CN108663189A (en) * 2018-06-13 2018-10-16 西南交通大学 Running train model balance mounting device in a kind of adjustable wind tunnel test
US20220060083A1 (en) * 2018-12-17 2022-02-24 Gree Electric Appliances, Inc. Of Zhuhai Power consumption control device, magnetic levitation system, and power consumption control method
US11555679B1 (en) 2017-07-07 2023-01-17 Northrop Grumman Systems Corporation Active spin control
US11573069B1 (en) 2020-07-02 2023-02-07 Northrop Grumman Systems Corporation Axial flux machine for use with projectiles
US11578956B1 (en) 2017-11-01 2023-02-14 Northrop Grumman Systems Corporation Detecting body spin on a projectile
US20230094251A1 (en) * 2021-09-27 2023-03-30 Novium Taiwan Inc. Detachable supporting device

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7379206B2 (en) * 2004-01-12 2008-05-27 Xerox Corporation Methods and systems for determining resource capabilities for a lean production environment
CN102445220A (en) * 2011-09-29 2012-05-09 中磁力（深圳）科技有限公司 Method and device for detecting position of suspended substance in magnetic suspension device
CZ304430B6 (en) * 2012-12-05 2014-04-30 Vysoká Škola Báňská-Technická Univerzita Ostrava Levitation-vibrating device for measuring viscosity, density and interfacial tension
CN105752796B (en) * 2016-04-29 2017-11-28 西安交通大学 A kind of used during elevator falling lower speed life-saving device and method based on shear thickening liquid
CN110244243B (en) * 2019-06-17 2024-01-30 西南交通大学 Rotary permanent magnet electric suspension and driving integrated testing device
CN110726461B (en) * 2019-12-18 2020-03-27 常州莫森智能科技有限公司 Full-automatic high-precision dynamic electronic weighing device
CN113418741B (en) * 2021-08-24 2021-10-29 海门兴虹环保科技有限公司 Mining tunnel survey measuring equipment and measuring method with accurate detection
CN114199354A (en) * 2021-11-29 2022-03-18 江苏大学 Self-adaptive magnetic suspension electronic balance and weighing method thereof
CN114435139B (en) * 2022-04-08 2022-06-17 西南交通大学 Magnetic repulsion type suspension pantograph

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4191951A (en) * 1977-05-16 1980-03-04 Caterpillar Tractor Co. Device for sensing fluid forces
US4619146A (en) * 1981-05-22 1986-10-28 William Banko Flow meter
US4698562A (en) * 1983-10-04 1987-10-06 Eaton Corporation Motor electrical positioning system and the application thereof within vehicle traction drives
US5168183A (en) * 1991-03-27 1992-12-01 The University Of British Columbia Levitation system with permanent magnets and coils
US5294757A (en) * 1990-07-18 1994-03-15 Otis Elevator Company Active vibration control system for an elevator, which reduces horizontal and rotational forces acting on the car
US5308938A (en) * 1990-07-18 1994-05-03 Otis Elevator Company Elevator active suspension system
US5321217A (en) * 1990-07-18 1994-06-14 Otis Elevator Company Apparatus and method for controlling an elevator horizontal suspension
US5359490A (en) * 1989-08-24 1994-10-25 Kabushiki Kaisha Yaskawa Denki Seisakusho Method of controlling moving element of magnetic levitation and transport system
US5379864A (en) * 1993-11-19 1995-01-10 Otis Elevator Company Magnetic system for elevator car lateral suspension
US5491633A (en) * 1991-05-20 1996-02-13 General Motors Corporation Position sensor for electromechanical suspension
US5980193A (en) * 1996-09-18 1999-11-09 Magnetic Bearing Technologies, Inc. Magnetically levitated robot and method of increasing levitation force
US6035703A (en) * 1998-09-23 2000-03-14 Abnett; Albert C. Low viscosity measurement adapter for an orbiting object viscometer
US6353273B1 (en) * 1997-09-15 2002-03-05 Mohawk Innovative Technology, Inc. Hybrid foil-magnetic bearing

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4191951A (en) * 1977-05-16 1980-03-04 Caterpillar Tractor Co. Device for sensing fluid forces
US4619146A (en) * 1981-05-22 1986-10-28 William Banko Flow meter
US4698562A (en) * 1983-10-04 1987-10-06 Eaton Corporation Motor electrical positioning system and the application thereof within vehicle traction drives
US5359490A (en) * 1989-08-24 1994-10-25 Kabushiki Kaisha Yaskawa Denki Seisakusho Method of controlling moving element of magnetic levitation and transport system
US5294757A (en) * 1990-07-18 1994-03-15 Otis Elevator Company Active vibration control system for an elevator, which reduces horizontal and rotational forces acting on the car
US5308938A (en) * 1990-07-18 1994-05-03 Otis Elevator Company Elevator active suspension system
US5321217A (en) * 1990-07-18 1994-06-14 Otis Elevator Company Apparatus and method for controlling an elevator horizontal suspension
US5168183A (en) * 1991-03-27 1992-12-01 The University Of British Columbia Levitation system with permanent magnets and coils
US5491633A (en) * 1991-05-20 1996-02-13 General Motors Corporation Position sensor for electromechanical suspension
US5379864A (en) * 1993-11-19 1995-01-10 Otis Elevator Company Magnetic system for elevator car lateral suspension
US5980193A (en) * 1996-09-18 1999-11-09 Magnetic Bearing Technologies, Inc. Magnetically levitated robot and method of increasing levitation force
US6353273B1 (en) * 1997-09-15 2002-03-05 Mohawk Innovative Technology, Inc. Hybrid foil-magnetic bearing
US6035703A (en) * 1998-09-23 2000-03-14 Abnett; Albert C. Low viscosity measurement adapter for an orbiting object viscometer

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080218929A1 (en) * 2002-09-27 2008-09-11 Harold Davis Magnetic levitation apparatus
US7505243B2 (en) * 2002-09-27 2009-03-17 Levitation Arts, Inc Magnetic levitation apparatus
CN102680356A (en) * 2012-05-25 2012-09-19 东北大学 Density measuring device and method based on electromagnetic suspension
DE102016205377B3 (en) * 2016-03-31 2017-08-03 Festo Ag & Co. Kg Measuring arrangement and method for operating a measuring arrangement
WO2018094401A1 (en) 2016-11-21 2018-05-24 Flyte Llc Interactive and customizable device using magnetic levitation
US11555679B1 (en) 2017-07-07 2023-01-17 Northrop Grumman Systems Corporation Active spin control
CN107589141A (en) * 2017-09-06 2018-01-16 南京工业大学 One kind is used for edible oil quality detection method based on magnetic levitation technology detection object density
US11578956B1 (en) 2017-11-01 2023-02-14 Northrop Grumman Systems Corporation Detecting body spin on a projectile
CN108663189A (en) * 2018-06-13 2018-10-16 西南交通大学 Running train model balance mounting device in a kind of adjustable wind tunnel test
US20220060083A1 (en) * 2018-12-17 2022-02-24 Gree Electric Appliances, Inc. Of Zhuhai Power consumption control device, magnetic levitation system, and power consumption control method
US11573069B1 (en) 2020-07-02 2023-02-07 Northrop Grumman Systems Corporation Axial flux machine for use with projectiles
US20230094251A1 (en) * 2021-09-27 2023-03-30 Novium Taiwan Inc. Detachable supporting device

Also Published As

Publication number Publication date
US20020124765A1 (en) 2002-09-12

Similar Documents

Publication Publication Date Title
US6595041B2 (en) Method and apparatus for magnetic levitation
KR100827738B1 (en) Non-contact convey device by superconducting magnetic levitation
EP0857945B1 (en) Ferrofluid sensor
EP1958323B1 (en) Magnetic levitation system
US4398773A (en) Magnetic suspension assembly for a rotor
CN100544183C (en) Magnetic-repellent suspension device
EP0983450B1 (en) Bearing device
US8169114B2 (en) Large gap horizontal field magnetic levitator
CN100544184C (en) Magnetic-repellent suspension device with vertical mobile controlling organization
JPH09501498A (en) Inclinometer
JP6440740B2 (en) Device for holding, positioning and / or moving objects
Jones et al. Simple theory for the Levitron®
CN1822487B (en) Magnetic expelling type suspension device
US6799462B1 (en) Gravimetric measurement method and system
Yu et al. Boundary interface condition of magnetic fluid determines the magnetic levitation force experienced by a permanent magnet suspended in the magnetic fluid
Hilber et al. A magnetic membrane actuator in composite technology utilizing diamagnetic levitation
JP2009527207A (en) Levitating equipment
CN102055382B (en) Repelling magnetic suspension system
CN2901689Y (en) Magnetic expelling type suspension device
US20040244486A1 (en) Inertial navigation device for ion propulsion driven spacecraft
CN2894076Y (en) Magnetic repelling suspension device with vertical moving control mechanism
JPH05508916A (en) Ultra-compact strategic angular velocity sensor
US11041878B2 (en) Three dimensional sensing element suspension method and measurement system
Rivetti et al. Turbine flowmeter for liquid helium with the rotor magnetically levitated
WO2019173160A1 (en) Compact and highly sensitive gravity gradiometer

Legal Events

Date Code Title Description
REMI Maintenance fee reminder mailed
FPAY Fee payment

Year of fee payment: 4

SULP Surcharge for late payment
FPAY Fee payment

Year of fee payment: 8

REMI Maintenance fee reminder mailed
LAPS Lapse for failure to pay maintenance fees
STCH Information on status: patent discontinuation

Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362

FP Lapsed due to failure to pay maintenance fee

Effective date: 20150722